The invention belongs to the technical field of suction fans and exhaust fans, and particularly relates to a self-cleaning type exhaust fan. The self-cleaning type exhaust fan comprises a shell, an air outlet screen cover, an air inlet screen cover, a motor, fan blades, a scraping module, an impact module and dust discharging modules. The scraping module is connected to one side of the air inlet screen cover in a matched mode, and used for scraping and removing dust on the surface of the air inlet screen cover. The impact module is arranged in the middle of the air inlet screen cover, matchedwith the scraping module and used for beating and removing the dust on the surface of the air inlet screen cover. The first structure of the impact module comprises a support, a first telescopic rod,a first spring, a press block and a sliding ring. The second structure of the impact module comprises a second telescopic rod, a fixing ring, a second spring and arc-shaped plates. The dust discharging modules are arranged on the two sides of the lower end of the air inlet screen cover. According to the self-cleaning type exhaust fan, the impact module is matched with the scraping module to beat and remove the dust on the surface of the air inlet screen cover, the dust discharging modules are arranged to discharge the dust removed by the scraping module and the impact module, and therefore thecleaning effect of the exhaust fan is improved.